1. Field of the Invention
The present invention relates to a latch especially well suited for locking a hinged window in the closed position. The inventive latch includes an electrical switch which is actuated when the latch is released. This makes the latch particularly useful for employment in emergency escape portals such as windows, doors, or hatches.
The emergency exit latch constructed in accordance with the present invention may be advantageously used in a number of applications, such as public conveyances, school buses, recreational vehicles, or any other application requiring the use of an emergency signal when a portal is opened. When the latch is operated, the switch associated with the latch is actuated. This condition may be sensed by appropriate circuitry and used to drive an emergency indicator which would notify the vehicle's operator of the condition.
2. Description of the Prior Art
In the past, when it was desired to provide a portal with a warning to indicate that a window was unlocked, the problem was solved by directly coupling an electrical switch to the window. For example, in the case of a bus window of the type which is latched on the bottom and hinges from the top, a simple push-button switch was mounted adjacent the top of the window in such a manner that when the window is properly secured in the frame, the window itself would depress the actuating element of the switch. Thus, when the window became unlocked, it would swing open from the bottom, insofar as in this situation it is secured only at the top portion of its frame. If the window were to swing open a sufficient amount, it would move to a position where it would no longer actuate the switch and would signal the operator of a dangerous condition. Although the provision of such a switch results in some improvement over a window without any safety feature, this technique suffers from a number of inadequacies. For example, the switch is not actuated until the window is actually unlocked and begins to swing about dangerously. It is even possible that the window may become unlatched and swing about without notifying the operator of the condition due to the fact that it does not swing out enough to actuate the switch.